Work-engaging support for surface-treating machines



A, A. CLARKE.

WORK ENGAGING SUPPORT FOR SURFACE TREATING MACHINES.

APPLICATION FILED JAN.13. 2920 1,366,633. 'PatentedJan. 25, 1921.

ATTORNEY ALEX A. CLARKE, 01!. DALLAS, TEXAS.

WORK ENGAGING SUPPORT FOR SURFACE-TREATING MAUHII NES Specification of Letters Patent.

Patented Jan. 25, 1921.

Application filed January 13, 1920. Serial No. 351,156.

T 0 all whom it may concern:

Be it known that I Apex A. CLARKE, a citizen of the United States, residing at Dallas, in the county of Dallas and State of Texas, have invented certain new and useful Im rovements in Work-Engaging Supports or Surface-Treating Machines, of which the following is a specification.

This invention relates to new and useful improvements in work engaging supports for surface treating machines.

This invention has articularly to do with surface treating mac ines involvin a re volving surface treating member. he idea involved is to provide an adequate support both in advance of and followin the revolving member whereby the machine is held steadil and evenl I and the entire surface extending to the e es of the work, may be treated'without variation in finish or deviation in depth of out. It is obvious that the work or finishing or removing afinish from a fiat surface, must be erformed in courses or parallel paths and if the revolving surface treating member was permitted to tilt down at one end, uneven and scored work would be done. It is the object of the invention to do the work in courses and to do it so perfectly, that the courses may be over lapped without visible efiect after the work is completed.

In carrying out the invention a base member is provided a transverse opening intermediate its ends, for receiving a surface treatin drum and exposing the underside of the latter to the work. That portion of the base in front of the opening may be termed the advance portion and that portion in rear of the opening, may be termed the following or trailing portion. One of the features resides in providin a shoe on the following portion of less wi th than the advance portion and also of a width less than the length of the drum; whereby the following portion will always be supported upon worked surface and the chance of being supported partly on worked or sanded surface and partly upon unworked surface, which would tilt the device and cause the drum to cut deeper at one side, is eliminated. The advance portion and the shoe may each have a covering of soft fabric or other suitable material to hold the metal out of con tact with the working surface and prevent marring of the latter. These coverings may be suitably fastened so as to be removable.

The invention will be more readily understood from a reading of the following specification and by reference to the accompan ing drawings, in which an example of t e invention is shown, and wherein:

Figure 1 is an elevation of a surface treating machine equipped with a base constructed in accordance with thisinvention,

Fig. 2 is a plan view of the base,

Fig. 3 is an underside view of the same,

Fig. 4 is a longitudinal sectional view on the line 4-4 of 1* ig. 2, and

Fig. 5 is a transverse sectional view on the line 55 of Fig. 4-.

In the drawings the numeral 10 designates an elongated base member which I preferably form as a plate with an upstanding marginal flange 11 on its upper side, extending entirely around the plate. At the central portion of the plate a transverse opening or slot 12 is provided. At each end of the slot the flange 11 is built up at 13 and in wardly directedears Mare made integral with the portionl fia'ngell and base plate. These ears receive the lower ends of posts it which are fastened therein by set screws 15 or any other means. The manner of at taching the base to the machine is optional and may be changed in accordance with the machine used.

have shown a frame 16 vertically adjustable in the posts and provided with a motor driven drum 1? which latter projects through the slot 12. The frame and drum form no part of this invention, but are fully shown and described in my application on surface treating machine filed Feb. 13, 1920, Serial No. 358,485. The drum is rapidly revolved and has a surface covering 0 sand paper, or polishing cloth or other material according to the class of work to be done. Machines of this character are used in sanding new and old wooden surfaces and also for polishing finished surfaces.

The machine is moved in direction of the arrows. The rear or following portion 18 is cut away on each side of a central longitudinal shoe 19 extending from the slot 12 to the rear edge of the plate. This shoe has a width considerabl less than the length of the drum 17. The a Vance portion 20 of the plate, which is that portion lying in advance of the slot, is flush with the under surface of the shoe. A strip of soft fabric 21 is employed as a covering for the advance portion and a similar strip 22 is used to cover the shoe 19. Each strip has one end passed up through the slot 12 and folded back over a transverse rib28 contiguous to the edge of said slot; While the other end of the strip is folded over the flange 11 at the end of' the plate. Transverse fastening bars 24 are pressed against the ends of the cloth by eccentric latches 25 pivoted on studs 26 projcrting up from the plate 10. The latches are confined on the studs by nuts 27. By turning the latches the ends of the strips are released and the strips may be removed or tightened. It is obvious that the manner of fastening the ends of the strips permits of great variation.

When the machine is in use the strip 21 of the advance portion 20 is always resting on the treated surface; while the strip 22 of the shoe is resting on the surface which has been treated. By makin the strip 22 and shoe l9 narrow so that he ends of the drum project on each side of the said parts and by elevating the portion 18 from the center of the slot 12 rearwardly, all liability of the rear portion of the base resting on an untreated portion of the surface, is obviated. It is obvious that if the surface was being removed to a depth of -fof an inch and one side of the rear portion rested on uncut surface and the other on cut surface, the drum would be disposed of an inch lower at one end then at the other end, consequently an uneven cut resulting in scores would be had. The ad vance portion is ample enough to firmly support the machine on the margin of a surface and as the machine is moved forward the drum will be carried onto the ed e of the surface. Likewise the shoe is suicient to support the machine until the Work is carrlcd to the opposite edge. By the arrangement the entire surface may be worked.

What 1 claim, is:

In a machine of the character described, a base having a substantially flat advanced portion and a trailing portion, said base having a transverse opening between said portions, said advanced. portion extending for substantially the entire length of the transverse opening, a frame arranged upon and carried by the base, a rotatable surface treating element carried by the frame and pro ecting into the transverse opening and extending downwardly beyond the opening,

means to drive the rotatable surface treatc ing element, and a shoe carried by and de pending from the trailing portioin said shoe lntving its longitudinal edges disposed inwardly for substantial distances from the ends of the rotatable surface treating ele ment so that either longitudinal edge may be vonveniently retained out of engagement with the untreated portion of the Surface.

In testimony whereof I afiix my signature.

ALEX A. CLARKE. 

